Having ran a couple where I invited a couple of prem teams, I spoke to multiple prem players before I announced it about the map pool as I wanted to put some non played maps in (specifically subbase as its my favorite map) and they all said they wouldn't be able to get a team of 6 to play these maps.
I think the only way to actually get top players to play these maps would be to throw up a pretty big prize pool, maybe a few people come together and make a large prize pool? I know for myself I'd be happy to throw a couple hundred bucks in but im not footing a 5k bill like the jump world cup and I don't expect any other individual to do so.